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Sex in the Sun May Increase Your Fertility

Tim Boyer's picture
Sexual Health

Fertility problems plague approximately 15% of couples attempting to conceive. Population studies show that of the 15% affected, about 30-40% of infertility is attributable to the male’s health with the remaining 70-60% due to the female’s health.

One recent study posits that both men and women may share a common cause of infertility that could be remedied by something as simple as sex in the sun. Discover what sex in the sun may have to do with increasing your fertility.

In a recent issue of the European Journal of Endocrinology, researchers Elisabeth Lerchbaum and Barbara Obermayer-Pietsch from the Department of Internal Medicine, Medical University of Graz, Austria performed a retrospective study concerning fertility by focusing on biological processes important to human sexual reproduction associated with levels of Vitamin D.

Vitamin D is a steroid hormone whose precursor is found in the skin and is converted to its active form through a biochemical reaction in response to exposure to the UV-B rays from the sun. Approximately 80-90% of the Vitamin D in our circulation is derived from sunlight.

While Vitamin D is well-known for its function in maintaining calcium and phosphorus homeostasis and promoting bone mineralization, what is lesser known is that vitamin D receptors are present in a wide range of tissues including reproductive tissues and therefore may possibly play a role in modulating reproductive processes in both men and women. Vitamin D can achieve this by acting as a transcriptional activator or co-factor when the activated form of Vitamin D binds to a Vitamin D receptor in a specific tissue and initiates a biological process.

In the study, data was mined from PubMed—a database of over 21 million citations related to biomedical literature from MEDLINE, life science journals and online books. Using keyword search phrases such as “vitamin D” and “fertility,” “vitamin D” and “reproduction,” etc., the authors of the study reviewed relevant articles and analyzed the data regarding what previous research has revealed about the interconnectedness of fertility with Vitamin D.

What the researchers found in the literature were multiple studies that showed that both men and women possess vitamin D receptors in a wide variety of tissues related to sexual reproduction and that expression of the receptors has been detected in association with steroidogenesis of sex hormones important to reproduction.

For example in male sexual organs, studies have shown that Vitamin D receptors and vitamin D metabolizing enzymes are concomitantly expressed in spermatids, vesicles within the epididymis, seminal vesicles and prostate gland as well as in human sperm. Vitamin D is believed be involved in not only increasing sex hormone production, but also in maturation of sperm involving motility and the acrosome reaction when a sperm comes in contract with an egg.

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Studies involving Vitamin D and female sex organs demonstrate that Vitamin D plays a role in sex hormone production and endometrial development in preparing the uterus for implantation of a fertilized egg.

Furthermore, the researchers discuss the results of animal studies that demonstrated that Vitamin D deficient rats were sub-fertile with numerous sperm quality problems, which following treatment with Vitamin D were able to mate successfully afterward. Animals engineered as knockouts lacking the genes for Vitamin D receptors, likewise presented with infertility and developmental problems associated with sexual development.

The authors also point toward more limited data involving seasonal changes with decreased sunlight exposure and decreased Vitamin D levels and decreased fertility.

They tell us that blood levels of Vitamin D show seasonal variation with high levels in the summer and autumn and lower levels during winter and spring. Furthermore, that in northern countries, where a strong seasonal contrast in available sunlight exists, the conception rate is decreased during the dark winter months, whereas a peak in conception rates during summer leads to a maximum in birth rate in the spring. And, moreover, that ovulation rates and uterine receptivity appear to be reduced during prolonged sun-starved winters in the northernmost countries.

However, in studies involving in vitro fertilization (IVF) and Vitamin D levels, there have been both positive and negative associations between fertility and Vitamin D. Furthermore, other studies have found an inverse correlation with supplemental Vitamin D and lowered levels of estradiol and progesterone. These studies are in contrast to other studies in men that showed increased levels of testosterone associated with Vitamin D and that sperm appear to benefit from higher levels of Vitamin D.

While the evidence supporting the authors’ hypothesis that Vitamin D deficiency might play a role in endocrine disturbances and thereby affect fertility, the authors do note that the evidence they present is primarily from animal studies and observations, and not from experiments designed specifically for determining the relationship between Vitamin D and fertility.

However, they do believe that the data presents encouraging evidence that warrants further investigation into the associated link of infertility and Vitamin D and that potential therapeutics involving supplemental Vitamin D may prove beneficial as well as safe and relatively expensive in comparison to invasive IVF treatments.

Although, the authors do not directly promote the idea of sex in the sun as a way to increase your fertility, you have to admit that with approximately 80-90% of our Vitamin D in our circulation being derived from sunlight exposure, the idea does present a good reason to go outdoors and enjoy the scenery.

Image Source: Courtesy of Wikipedia

Reference: "Vitamin D and fertility--a systematic review" European Journal of Endocrinology 2012; Elisabeth Lerchbaum and Barbara Obermayer-Pietsch



WOW! its amazing. Thank you very much for the valuable info sharing with others about the sex fertility. A big thank you for this post and to your website.
Well, why not promote sex in the sun? Sounds lovely to me -errr - with limited ....exposure that is.. :)